Why heterosis levels can be equal...

[ANAZAZI]

The heterosis effect is basically the benefit of having as many heterozygous loci as possible.
Heterozygous means that on a given locus (the place where genes are located), there are two different genes.
Homozygous means that a locus has two copies of the same gene.

Where there are two different genes on the same locus, usually the gene that provide the individual with the most vigour dominates the other gene (the HETEROSIS EFFECT).
To get full individual heterosis it only takes two breeds, not three or four, but two is enough.

Putting more than two breeds in the mix will start hurting consistency.
Putting more breeds than two in the mix will not hurt heterosis one bit, as long as all three or four breeds are unrelated. Thus; heterosis is maximized in all these crosses, and will only diminish by crossing with a related breed, such as putting brangus on a angus cross, for example.

Maternal heterosis, where a mother cow is more fertile, lives longer, milks more e.t.c. than non crossbred cows, is best used by adding a third breed to sire the calf. The calf then gets the benefits of a crossbred mother plus the benefits of being crossbred himself.

In a feedlot situation however, there is no extra performance from 3ways than from 2ways, and a 4way crossed calf will perform as good.
They are all maximally heterozygous, all take advantage of hybrid vigour.
The 3way and 4way also benefitted from having a crossbred mother before they were weaned, and they are also less consistant than 2way crosses, consistancy is important in many situations, but has nothing to do with heterosis...

 

[Old_man_emu]

Great post! I am somewhat surprised that noone has tried to argue this one, but then maybe tier is no arguement to be had.

On the maternal influence, if it only stays with the calf until weaning, is it fair to say it's in the milk? I just don't understand that what other influence the cow has once the calf is born particularly when you an f1 calf will perform just as well post weaning.

And finally, does using a gert cow in a crossbreeding system give the same maternal result as a 3 way cross?

 

[cow pollinater]

such as putting brangus on a angus cross, for example...

I wasn't going to say anything for at least a while but now that we've all listened to the crickets for awhile I'll ad my little :2cents: ... I think brangus and angus have been going seperate ways long enough that the genetics of most mainstream cattle are dissimilar enough to give good heterosis. The original angus influence in brangus are not the same cattle as what the angus breed has turned into.
Other than that, :nod: . Back to listening to the crickets.

 

[Dylan Biggs]

Anazazi, the more homozygous the parents, ie linebred, the more heterosis in the cross?

Anazazi, good post.

When you you refer to consistency being reduced by more than a 2 way cross what traits are you considering?

Do you think it is posssible to quantify the presumed increase in fertility from heterosis seperate from the level of fertility bred into the parent stock to begin with.

Have you considered closed populations that exhibit a high degree of fertility may not benefit from any increase in fertiltiy from being crossed.

Might it be that the increase in fertility due to heterosis in the cross, is as much a reflection of a mediocre level of fertility in the parent stock to begin with?

 

[double v]

I though the goal was hybrid vigor as a breeder , good post but i don't think we need to keep reminding these folks of that just look at some of post and you can see that most don't follow. keep it up it keeps the breeds kicking....

 

[cow pollinater]

Do you think it is posssible to quantify the presumed increase in fertility from heterosis seperate from the level of fertility bred into the parent stock to begin with.?

It is possible. I don't have any hard numbers at hand but its been proven a few times over in dairy herds. There was a push for heterosis in dairy cattle for awhile and they keep records like beef guys can't even imagine. The most standard cross has been holstien/swedish red/jersey and then back to holstien. fertility and health traits go through the roof on the first cross and it stays that way with minimal drop in production.
We had a few dairymen who looked at that cross and decided to stay a little closer to holstein and tried using red and white and ayshire(not know for being high fertility) and had similar results of increased fertility above and beyond the parent stock.

 

[ANAZAZI]

Anazazi, the more homozygous the parents, ie linebred, the more heterosis in the cross?

This has been argued many times at "the dark side", I suppose so, considering two linebred strains of somewhat related breeds like two british breeds, the more linebred the strains, the less likely is it that they share the same genetics by chance.

 

[thommoos]

What about composite Breeds like Beefmaster, a mix of Brahma, Shorthorn, Herf. With the advent of breeding up, in this case adding black, whether angus or simm, what would you cross breed to, the reason I ask is I know there is angus or simm in black beefmasters, I hear tell char in some others, what to breed or cross breed to achive maximum heter without losing consistency. That makes 5 maybe 6 breeds.

 

[Massey135]

Heterosis is maximized at the third cross. Not fourth, not fifth. In terms of performance, the 3 breed individual expresses the most hybrid vigor. Perhaps you need to call Texas A &M and Kansas State University and inform them of your newfound mongrel discovery. I'm looking at articles written by professors at both schools, and they both support what I'm saying and dispute what your saying.

 

[Massey135]

What about composite Breeds like Beefmaster, a mix of Brahma, Shorthorn, Herf. With the advent of breeding up, in this case adding black, whether angus or simm, what would you cross breed to, the reason I ask is I know there is angus or simm in black beefmasters, I hear tell char in some others, what to breed or cross breed to achive maximum heter without losing consistency. That makes 5 maybe 6 breeds.

Composites were never intended to be used in a crossbreeding program. They were created so that you could just breed beefmaster x beefmaster as opposed to having to keep and cross seperate purebred lines in order to achieve hybrid vigor. I think composite x composite retains 87% of the hybrid vigor expressed in the F1.

 

[Taurus]

And it took 7 days for Gassey to say something about it....

 

[ALACOWMAN]

Heterosis is maximized at the third cross. Not fourth, not fifth. In terms of performance, the 3 breed individual expresses the most hybrid vigor. Perhaps you need to call Texas A &M and Kansas State University and inform them of your newfound mongrel discovery. I'm looking at articles written by professors at both schools, and they both support what I'm saying and dispute what your saying.

why didnt you dispute it on the 23rd, when he first opened this thread?? this was in responce to your question

 

[ALACOWMAN]

And it took 7 days for Gassey to say something about it....

you owe me a beer :cowboy:

 

[Taurus]

And it took 7 days for Gassey to say something about it....

you owe me a beer :cowboy:

here you goes!

 

[Massey135]

Heterosis is maximized at the third cross. Not fourth, not fifth. In terms of performance, the 3 breed individual expresses the most hybrid vigor. Perhaps you need to call Texas A &M and Kansas State University and inform them of your newfound mongrel discovery. I'm looking at articles written by professors at both schools, and they both support what I'm saying and dispute what your saying.

why didnt you dispute it on the 23rd, when he first opened this thread?? this was in responce to your question

Been in pre con meetings all week, finally found some CT time.

And ALA, teaming up w/ Taurus is terrible for your credibility. Anyone that presents themselves with his choice of words has very little to offer...in general.

 

[Taurus]

Heterosis is maximized at the third cross. Not fourth, not fifth. In terms of performance, the 3 breed individual expresses the most hybrid vigor. Perhaps you need to call Texas A &M and Kansas State University and inform them of your newfound mongrel discovery. I'm looking at articles written by professors at both schools, and they both support what I'm saying and dispute what your saying.

why didnt you dispute it on the 23rd, when he first opened this thread?? this was in responce to your question

Been in pre con meetings all week, finally found some CT time.

And ALA, teaming up w/ Taurus is terrible for your credibility. Anyone that presents themselves with his choice of words has very little to offer...in general.

Yet you still post in other threads during that period.....at last ALA has some credibility where you have none left.

 

[Anonymous]

I know for a fact he at least viewed this thread. I opened it in the first day or 2 and his name was at the bottom as viewing it. Probably took him this long to find 2 articles that supported his viewpoint

 

[chippie]

I know for a fact he at least viewed this thread. I opened it in the first day or 2 and his name was at the bottom as viewing it. Probably took him this long to find 2 articles that supported his viewpoint

yet he did not post a link to the articles. I would be interested in reading them.

 

[Taurus]

I'm still waiting for his explanation about how his cattle can change the markings.

 

[sim.-ang.king]

I know for a fact he at least viewed this thread. I opened it in the first day or 2 and his name was at the bottom as viewing it. Probably took him this long to find 2 articles that supported his viewpoint

yet he did not post a link to the articles. I would be interested in reading them.

Give him time...him and Sir lion are working hard to make up....I mean find this information.